Rolling mill installation



Oct. 20, 1931. M, A ,MQCREARY 1,828,426

ROLLING MILL INSTALLATION A Y Filed April 14, 1930 4 Sheets-Sheet l NjC)l jr .Z 45 'Ww-*O-G-o-O-O-O-oooooooooo Oct. 20, 1931. M. A. MCCRARY IROLLING MILL INSTALLATION l Filed April 14. 1950 4 Sheets-Sheet 2 Oct.20, 1931. M. A. MGCREARY 1,828,426

ROLLING MILL INSTALLATION Filed April 14. 195o sheets-sheet sv Oct. 20,1931. M. A. MccREARY Y 1,828,426

ROLLING MILL INSTALLATION Filed April 14, 1950 4 SheetsSheet 4 @lg u m-Q N QQ N 25% w i Q QN fw.

8 8&1 8 O om Patented Oct. 20, 1931 UNITED-*STATES PATENT oFFlcE MILLERA. MCCREARY, F-DANV1LLE, rLLINoIs, ASSIGNOR To THE zinc COMPANY, orDANVILLE, ILLINOIS, a ooRronATIoN or 'ILLm'ois Y RoLLrNcl MILLApplication flied April 14,

' This inventionA relates-to rolling Amill .installations particularlydesigned and adapted for rolling or :breaking-down. slabs of Zincmetalto form strips of suitable thick- V ness for coiling, comprising arolling .mill proper, a rollerstable adapted for deliver-` ing slabs tothe rolling mill, a catchers table adapted to receive the slabs afterthey have passed through the rolling mill, a return tal ble adaptedtoreceive slabs from the catchers table and to deiiver them at the frontor entering side of the rolling lmill proper, and a slab Wheel adaptedto deliver the slabs from thereturn tabletoithe rollers table to l5 beagain passed through the rolling'mill, this operation being Arepeatedvuntil the slabs have been broken-downto aid'esiredthifckf. ness.

Considered broadly, all "of the 'foregoing features and elements. areold and Well known and Willreadily be lunderstood by persons familiarwith the artifrom4 an in speetion of the drawings and Without a ole--rscription thereof in detail. f Y

As is generally Welllniown,`the operation of rolling or breaking downzinc slabs into strips of suitable thickness forl coiling, is: eiectedby passing it through therolling mill as many times .as maybenecessaryfto :educe .it to the thickness desired, this operation, inaccordance 'with the present invention, necessitating the d elivery,c'fL the slabs, after each rolling operation from fthe de-. livery to theentering side of the rollingmill, and a primary object ofthe 'inventionnis to provide-,a rolling mill installation-` forV the purposesspeciied, designedand adapted for etecting continuous rolling of aplurality of Zincslabs -a practicable number being. up to ten (10) whichare successively passedK through. the rolling mill `in seri es. in whichmanual labor in handling the slabs is practically eliminated-exceptingfor. guiding the slabs and controlling their movementsthereby eiiectinga large saving in labor1 'cost ;l rendering the Work ottheoperativesmorev efficient through reduced eifo'rt on their part; 1 and alsorendering itfprac-ticable to operate on much heavier slabs thanheretofore, all of which factors have resulted in largely intheinstallation from the lower side of Fig.

iNsfrALLATIoN 1930,` sei-iai no. 444,258.

In the accompanying drawings, in which eo the invention is fullyillustrated,

Fig. 1, 1 is a diagrammatic top plan view of a rollingmill installationembodying my' invention and improvements. l f

,'Fig..2, 2 is' adiagrammatic side view of -65 i, i. y y

Figz, 3. is a diagrammatic side view, corresponding substantially toFig. 2, 2', of the return `table for delivering slabs after they have vpassedk through the rolling mill,

Vfrom the rearto the front side of the rolling mill preliminary tomaking another pass.

' Fig. 4 is a sectional AView substantially on At-h'e'line +4 of Fig. l.

l Fig. 5 is adetached perspective View illustrating a stop controlmechanism `for the slabs kas they are returnedto the front side' of therolling mill afterk passing through the saine. 1'

y Fig. 6 is a detail diagrannnatio vievv on the line 6--6 of Fig. l. Y y

Fig. 7 is a similar View on the line 7 7 of Fig. v1 ;V and f Fig. 8 isasectional View on the line 8-8 of Fig. l', illustrating means forimparting step-by-step rotation to the cooling Wheel.

For purposes oficlea'r and definite illustration and descriptionl Will'assume that my improved rolling millinstallation isr designed andadapted for rolling orbreakingdown slabs substantially 5- ft. long X 10in. Wide' X 2 in. thick and Which Weigh approximately 304 pounds.Obviously, however, the

dimensions andvveight of the slab admits of Wide variation 'dependingupon the kind of strip which is to be produced.

A rolling mill installation embodying my invention and improvementscomprisesa rollingmill, designated as a Whole, A. Rolling 10c millssuitable for the purpose may be purchased commercially and it is,therefore, unnecessary either to show or describe a rolling mill indetail.

Directly associated with the rolling mill A, one at the entering sideand the other at the discharge side thereof, are tables designated,respectively, as a whole, B, B, the table B being adapted to support theslabs 1n position for delivering them between the rollers of the mill A,and the table B being positioned to receive slabs from said rollingmill. c

In accordance with common practice, the tables B, B may be variouslyconstructed, for example, they may have smooth sheetmetal tops, eitherwith or without rollers and may be either inclined` or horizontal. Asshown, the rollers table B is downwardly inclined toward the rollingmill A and the catchers B is substantially horizontal, and both of saidtables are equipped with idle or anti-friction rolls.

Tables B, B are old and well known and can readily be furnished bymechanics skilled in the art and it is, therefore, unnecessary either toshow or describe said tables in dctail.

Having passed through the rolling mill A and been delivered upon thecatchers table B, the slabs are adapted to be returned to the front orentering side of the rolling mill and again passed through the sameuntil reduced or broken down to a desired thickness by suitable meansprovided for the purpose. As shown, said means are as follows:Positioned at one side of and in spaced relation to the rollers table Band catchers table B and extending lengthwise substantially co-vexpansive therewith, is a return table C upon which the slabs, aftereach pass through the rolling mill, are adapted to be delivered from thecatchers table B. As regards its general features, the table C is ofsubstantially the same construction as the rollers and catchers tablesB, B and can readily be supplied by persons skilled in the art, and needpotl, therefore, be shown or described in deyai To provide fordelivering slabs from the catchers table B upon the return table Cwithout lifting them, the top of said return table C is positioned at alower level than the top of the catchers table B, and extending fromsaid catchers table to said return table are inclined skids or slides c,the relation bein g such that slabs pushed sideways from the catcherstable B onto said skids or slides will decend along the same by gravityonto the table C, said table being provided with a spring stop o whichproject above the top of the table in position to stop said slabs and todefine their position on said return table.

As shown, said spring stop c consists of a bar 1 supported at the sideof the table C remote from the table B', said bar being supported at theupper ends of bars 2 pivoted to the floor or other supporting surface attheir lower ends, and which are held yieldingly in position by rods 3 towhich they are secured and which extend beneath the table C and throughholes formed in fixed supporting bars 4 secured to the frame of thetable C at the side thereof adjacent the table B. The pivot bars 2 -areyieldingly supported by coiled springs 5 inserted between the legs orsupports 4 and nuts or other heads 6 on said rods 8.

The table C comprises sections C, C2, the section C being downwardlyinclined to the horizontal from its extreme rear end to a pointsubstantially in line with the front side of the housing of the rollingmill A, and the section C2 being substantially horizontal, the topsurface thereof being only slightly above the floor or supportingsurface on which the rolling mill A is erected, and considerably lowerthan the top surface of the rollers table B.

As shown, the table C is equipped with rollers which, for the most part,are idle, so that slabs delivered upon said table from the catcherstable 1 will move along said table impelled by gravity only, or at most,will require very little force to move them endwise thereon. However, atabout the lower end of the inclined section C of said table, there are anumber of live rollers 02, which, as shown, are adapted to be driven bymeans of suitable driving connection with a motor 03, consisting, asindicated, of a counter-shaft 04, a pulley on which is belt connectedwith pulleys on the shafts of said rollers c2. As shown, said liverollers c2 are driven by a single belt adjusted back and forth overpulleys secured to the shafts of said live rollers and intermediate idlerollers rotatably mounted on suitable fixed studs, in a familiar manner.To provide for quickly and conveniently starting the rollers c2, and forstopping them when desired, the connection between the` armature shaftof the motor and the counter-shaft c4 is of a usual pulley and belttype. The pulley on the counter-shaft is relatively much larger thanthat on the armature shaft, in order to obtain a suitable speedreduction, and the pulley on the counter-shaft is adapted to be securedto and disengaged from said shaft by means of a suitable clutch adaptedto be thrown in and out of engagement by means of a manually operablelever c6.

It is found in practice that when the clutch which drives theCounter-shaft c4 is thrown out, the inertia of the live rollers c2 andtheir llo driving connections will effectively brake A' slabs passingalong the section C of the rcturn table, operating to stop and hold thesame until the driving clutch therefor is again thrown in.

`scriptiorry without a; further Installation of suitable driving meansfor the live rollers c2, together with suitable clutch mechanism,l canreadily be eftectedby skilled mechanics from, the foregoing deidescription thereof in detail. v Y l The -motor 03, counter-shaft ci*andasseciated mechanism will be mounted below the tops of the skids orslides c positioned Ain the corresponding portion of the return table C,

while the clutch operating lever 06is acces- -sibly Amounted at the sideof said'return table remote from the catchers tabley B', where it willnot obstruct movement of slabs from v I said catchers table tothe returntable.

" v Slabs on Vthe section C2 of thereturn table C, ,which issubstantially co-eXtensive with the rollers table B, are adapted to bedelivered from said return table to said rollers table to be againpassed through the rolling inill'A, by means of what for convenience maybe referred to as aslab or cooling wheel, designated as a whole, D,consisting of a shaft (Z rotatably mounted in suitable bearf ings formedon pillow blocks or pedestals cl.

" Secured to rotate with thc sliaftd 'are any desired number, as shown'eighteen, sets'or series of arms (Z2, the armsof each set or seriesfbeing.arranged tangent to circles concentric iviththeaxis of rotationof the shaft Z and spaced equalangular distances apart.

l/Vitlr the construction and relation ,de-V

scribed,inI whiclrthere are eighteen arms Z2 ineach set or series,theouter ends of `which ire spaced equal distances apart, it is obviousthat diametrically "opposite arms will' be parallel with each other.

In operation, step-bysstep idapted to be imparted to the Yslab wheel Dby means presently described, the relation being such that rotation ofsaid coolingwheel in the direction indicated by the arrow, Figs.

6 and 7, will cause the outer ends of the arms Z2" to' pass upwardlythrough spaces cl3 formed between separated portions of the section C2of the return table C, andthe relation being such, also, that duringperiods of rest of said cooling wheel, an arm cl2 of each l arms willextend substantially horizontal and will be `positioned in one of thespaces "d3 with its top edge slightly below the top of the section C2 ofsaid return table. Vith this construction, 1t is .obvious that when aslab is supported upon the section G2 of the return table in line withthe slabwheel C,` and rotation is imparted 'to said slab wheel, the'setsofV arms dz'directly beneath said slabl will raise the same throughwhat- ;ver arcsare traversed byV said arms at each intermittentactuation of said slab wheel.

and strengthened at their `inner `ends by rotatioir through arcs ofpredetermined length, is

thus rendering it possible for the rolling different sets or'- series ofarms Z2 are secured to discs Z4 rigidly securedto theshaft cl of saidwheel in any suitable manner, as by being bolted, welded,` brazed orotherwise `secured. thereto. Also, to impart desired strength, stiffnessand rigidity'thereto, said discs are provided at .theirouter edges withflanges d5, which conveniently can be formed by a usualstampingorswedging operation. As shown, also','the arms AParereinforced gussetplates which connect them to the discs to which they are secured,respectively.

Slabs moving along thereturntable C, between thearinsor spokes cl2 ofthe slab wheel, are adapted to be stopped ,in different positions aftertheir following ends have passed the housing of the roller mill A bysuitable stops al provided for the purpose which are adapted to bemanipulated manually by an operator. As shown, see particularly Fi gs.1,', 3 and 5, said stops d6 are mounted in holes or openings [Z7 inthedifferent parts i into Vwhich the section C2 of the return table Clisdivided by the spaces cl3, and consist of blocks 8 vsecured to stubshafts 7 rotatably mounted Vin anges formed at the lateral edges of theseparate parts of the section C? of the return table C.l In operation,rotation is adapted to be imparted to said shafts to cause the free endsof the stop blocks `8 seicured thereto to project through the holes or`openings @Z7 above the top of the return table section C2, by meansofcam arms 9 secured to said shafts,which project into the path ofmovement of plates 10/secured to a bar l1 supported so as to be movableendwise and to which endwiserniovement is adapted toV be imparted bymeans of a manually operable lever 12 which is adapted to be secured indifferent adjusted positions corresponding to the setting of a desired`stop block (Z6, by a usual quadrant locking mechanism 13.

At each pass. of the slab through thc rolling'inill A, it will be brokenVdown or reduced in thickness and correspondingly lengthened and theslab or cooling wheel D is made of av length substantially equal tothemaximum length of the slabs when rolled or brokendown to their finalthickness forcoiling. Thus, to save unnecessary handling of the slabs asthey are delivered from the reas practicable after the following ends ofsaid slabs have passed the housing of the roll ing mill A and, to effectthis, a pluralitypof stops ZG is providedwhich become effective los insuccession, beginning with the stop closest to the rolling mill andprogressively farther therefrom, as the length of the slab increases. Inaccordance with my invention, I effect this by a construction in whichsaid stops are set in succession beginning with the stop which isfarthest from the rolling mill and progressively towards the same, untilthe stop corresponding to any given length of slab is set.

Thus, after thefirst pass of the slab through the rolling mill, all ofthe stops Will be set in succession beginning vWith the stop farthestfrom the rolling mill and progressively towards the same, the number ofthe stops set after each pass, being gradually reduced as the slab isbroken down and becomes elongated until finally when the slab is fullybroken down, only the extreme stop Will be Set- To provide for thussetting said stop blocks, the plates on the bar 11 which cooperate withthe cam arms 9 on the shafts 7 to turn said shafts to raise the freeends of the stop blocks 8, are made of different lengths and are sospaced and positioned that said plates will contact With theircorresponding cam arms to set the stop blocks controlled thereby,respectively, at different intervals in the movement of the bar 11, thelengths of said plates 10, respectively, being such, also, that when thebar 11 is moved to effect engagement of any cam arm 9 with its operatingplate 10, said cam arm Will remain in engagement With said platethroughout the entire contemplated movement of said operating bar to setall of said stops. Y

Also, with the construction described, when all of said stops have beenthus set, they may be released so as to permit their return toinoperative position, by endwise movement of the bar 11 in a reversedirection from its movement to set said stops, said stops also beingreleased progressively in succession beginning With the stop nearest therolling mill. As step-by-step rotation is imparted to the slab orcooling Wheel D, in operation, it is obvious that when the arms on whichslabs are supported pass their vertical position, slabs supportedthereby Will turn by gravity so that they will rest on the arms Z2adjacent to and in front of arms or spokes on which said slab wasinitially supported and Will continue to rest upon and be supported bysaid arms until such time as said arms again pass horizontal position atthe top side of the wheel and become downwardly inclined at such anangle that the slabs will slide off from the same by gravity. With thisrelation, it is obvious that by properly positioning the slab or coolingWheel relative to the rollers table B, slabs discharged by gravity fromsaid Wheel Will beV delivered from the slab or cooling Wheel D onto therollers table B from being thrown OH from the same, said rollers tablepreferably Will be provided with spring stops or buffers which may besubstantially similar in construction and operation to those applied tothe return table C to prevent slabs delivered from the catchers table Bonto said return table from being thrown off from said return table.

In accordance With my invention, step-bystep rotation is adapted to beimparted to the slab or cooling Wheel D by means as follows Secured tothe shaft Z of said slab or cooling Wheel D so as to rotate therewith,is a ratchet Wheel 14 formed on opposite sides of Which arebearingsfitted to which, respectively, so as to turn freely thereon arerings 15, 15, which may be made of boiler plate or the like, both ofwhich are pivotally connected, respectively, by links 16, 16 With acommon pivot pin 17 secured in a pivoted lever 18.

The rings 15, 15 are each shaped to form projecting portions or lugs towhich, respectively, the links 16, 16 are pivoted, said links beingpositioned on opposite sides of a vertic l cal line through the centerof the ratchetl Wheel 14, and are proportioned so that they will projectbeyond the periphery of the teeth of the ratchet Wheel 14. Pivotallymounted upon the pivot pins Which connect the links 16, 16 to the ringsl5, 15 respectively, in position to engage the teeth of the ratchetWheel 14 are paWls 19, 19, the relation being such that upward movementof the free end of the lever 18 Will operate to advance the paWl 19causing it to engage a tooth of the ratchet Wheel 14 and thereby impartrotation to said ratchet Wheel, and thus to the shaft d of the coolingWheel, and to simultaneously retract the pavvl 19, While depression ofthe free end of the lever 18 will, in like manner, operate to advancethe paWl 19 and to retract the pawl 19 into position to engage the nextsucceeding tooth of the ratchet Wheel, both pawls 19, 19 operating torotate said ratchet Wheel and shaft in the same direction through equalarcs.

As installed for use, pivotal movement is adapted to be imparted to thelever 18 by means of a cylinder andpiston motor 20, opposite ends of thecylinder of Which are connected with a suitable source of supply offluid under pressure by a supply pipe 21 and branch pipes 22 and 23,communication of the pipe 21 and branch pipes 22 and 23 being controlledby a manually operated three-way valve indicated at 24. As shown, thevalve 24 is adapted to be operated by means of a hand lever 25accessibly located adjacent to the rollers table B.

As shown, the ratchet Wheel 14 has nine teeth and the paWl actuatingmechanism is so proportioned that at each full stroke of the piston ofthe motor 20, one of the pawls 19, 19, Will be advanced and the otherpawl retracted through an arc equal to one-half lob ` assn'med :andYheretofore described.

said-return tableC and deliver Y Lesegesspacing of the free ends ofthe-arms d? ofthe sl'abor cooling wheel/D yur'ider the conditions tToprovideifor'adjusting the throwofithe pawls 1Q, 19,the lever 18 isprovided at its pivoted end with a series of holes Q6, ar'- rangedyatfdifferent e distances `from thel pvot pin '17,fin`"whiclrsaid'pivotpinY is interchangeable. Thus, by shifting-the pivot pin from one" ofthefholes 26A to another, it is obvious thatthe throw of the pawls Vmaybe l' aried within considerable limits, to meet operatingconditions.

Y .'l" economize space and also to impart desired tall or pitch totheskids orslides c so that slabs willgdescend theysa'me lby gravity'from thecatchers,l tableB onto the. return lt'a'lile Cj, saidir'etnrntable is installedat an angle'togthewiollerls table B and catcherlstable BJidiverging from the end ofthe catchers table remoteromr therolling mill A tolwardsl the slab` or cooling. wheelD, which-,as

shown, lis .tapered to #conform to the divergence of lthe return table Cand the inclinationfof the rollers .table B. vDivergencefof the return`table Cl relative `to thet rollers table B .and catchers table is,renderedv necinLorder-to provide afslab orfcooling wheel D of properysize to-raisethe slabs from them onto `the inclined rollerstablegB, i,Y y 1f Y I I Obviously, however, to meetvvdiierent relativecondit-ionsotinstallation,the s lab or cbolingwheel D may 'be straight or tapered,horizontal, or. inclined, tofreceive `trom returntable.`l horizontal or"inclined, and Lto deliver Avto fa '.rollersY table, horizontalorincl-inedl,`'in1any combination. l

f- In 'l accordance with;` usual practice, the catchers table Bfcomprises apivoted section b which maybe raisedto provide fa space, insaid "catchers t'ableB tor-al portable coiling machine?,indicatedasiawhole, El j j- By zinctsla'bs'fas' used in Vthe foregoingspecification and within the 'scopeand' contemplation koit my invention,`Vit is my intention 'to include zincalloysfwhich contain :sui-

icient qua-n'tities"o'zinc so that they retain tliee'ssentialphysicalcharacteristics oi? zinc.

return table and automatically discharging them'npon the rollers table,f f V A- rolling millf installation? as Aspecified ranf'gedfbelowboththe rollersaiid catchers tables', and declinestowards the front `end ofthe installation.

8. A rolling mill installation as lspecified in claiml, in which thepower actuated trans- 'fer'. means is manually controlled. 4

. ,A rolling mill installation as specilied in' claim l, in which thepower actuatedtrans- 'er means'coinprisesa rotatable member and meansfor Vimparting step-by-step rotation i thereto. e

v5. In a rollingmill installation ofthe' type specified, the combinationof a rollerstable, a return table, a slab-wheel positioned betweensai-dreturntable and the rollers table,

comprising a shaft, `spaced series of arms secured to said shaft, each`series comprising the same number of arms all of `which are tangente toa circle-concentric lwith'the axis of said shaft, said return tablebeing provided with spacedopenings positioned and prov portioned vtopermit diiferent series of arms topass therethrough, respectively, andmeans applied to said shaft for imparting step-bvstep rotation to saidslab wheel, the rollers l table and the shaft of the slab Wheel beingpositioned above the section ofthe return table in transverse alignmenttherewith.

6. A rolling mill installation as specilied in claim5, in which themeans for imparting step-by-step rotation tothe slabwheel alsocomprisesmanually opera-ble control means.

7. A rolling millinstallationas specified in claim 5, whichalso'comprises a-catchers table positioned above vthe section of thewith,"and said section of said returntable is y downwardly i inclinedtowards the slab wheel, said installation also comprising downwardlyinclined skids from said catchers table to said return. table.`

l0. A rolling mill installationas specified in claiml 5, in which the.arms are so arranged that inpositions of rest ofthe slab wheel, an armof each series will extend substantially horizontal and will bepositioned only slightly'below the top of lthereturn table.

11. A rolling mill installationV as specified Vin claim 5, inwhichtliere .is aneven number ofar'ms eachvseries of slab supportingarms and the relation is such that in positions of rest of' the slabwheel an arm of each series iio iis

45 when their following ends attain positions GQ 1 hed in claim 5, whichalso comprises a stop will extend substantially horizontal ,and will beonly slightly below the top of the return table.

12. A rolling mill installation as specilied in claim 5, in which theslab wheel 1s so proportioned and positioned that as the arms thereofcome into substantially horizontal position after passing over the topof the wheel, an arm of each series in front of said horizontal arm willbe inclined downwardly at such an angle that a slab supported thereonwill be delivered onto the rollers table by gravity. K

13. A rolling mill installation as. specified in claim 5, in which theslab wheel is so proportioned and positioned that the arms of one seriescome to rest finally at such an angle of inclination that a slabsupported thereon will be delivered onto the rollers table by gravity.

14:. A rolling mill installation as spec-1- iied in claim 5, in whichVdiscs are secured to the slab Wheel shaft to which, respectively,different series of arms are secured.

15. A rolling mill installation as specified in claim 5, in whichmarginally flanged discs are secured to the shaft of the slab wheel towhich, respectively, different series of arms are secured.

16. A rolling mill installation as lspecified in claim 5, in which therollers table 1s downwardly inclined towards the rolling mill and theslab wheel is tapered and is installed with its large end remote fromthe rolling millV and its shaft diverging upwardly relative to thehorizontal and laterally relative to the catchers tablein. a directionaway from the rolling mill, and the return table also diverging from therollers and catchers tables.

17. A rolling mill installationas specified in claim 5, which alsocomprisesa stop mechanism consisting of a series of movably supportedstops adapted, respectively, to arrest movement of slabs along theVreturn table in claim 5, which also comprises a stop mechanismconsisting of a. series of movably supported stops adapted,respectively, to arrest movement of slabs along said'return table whentheir following ends attain positions in which they will clear therolling mill, and means for setting said stops in succession beginningwith the stop remote from the rolling mill.

19. A rolling mill installation as specimechanism consisting of a seriesof movably supported stops adapted, respectively, to arrest movement ofslabs along said return table when their following ends attain positionsin which they will clear the rolling mill, and manually operable meansfor setting said stops in succession.

20. A rolling mill installation as specified in claim 5, which alsocomprises a stop mech.- anism'consisting of a series of movablysupported stops adapted, respectively, to arrest movement of slabs alongsaid return table when their following ends attain positions in whichthey will clear the rolling mill, consisting of shafts rotatably mountedat the under side of the return table, stop blocks secured to saidshafts, respectively, the relation being such that turning movement ofsaid shafts will cause parts of said stop blocks to project above thereturn table, a manually operable lever and connection between saidlever and stop shafts for turning said stop shafts pivotally.

21. A rolling mill installation as specified in claim 5, which alsocomprises a stop mechanism consisting of a series of movably supportedstops adapted, respectively, to arrest Vmovement of slabs along saidreturn table when their following ends attain positions in which theywill clear the rolling mill, consistingof shafts rotatably mounted atthe under side of the return table, cam arms secured to said stopshafts, a bar mounted so as to be movable endwise, cam plates securedthereto adapted, respectively, to engage the camV arms on said shafts,and an operating lever connected to said bar.

22. A rolling mill installation as specified in claim 5, which alsocomprises a stop mechanism consisting of a series of movably supportedstops adapted, respectively, to arrest movement of slabs along saidreturn table when their following ends attain positions in which theywill clear the rolling mill, consisting of shafts rotatably mounted atthe under side of the return table, cam arms secured to said stopshafts, a bar mounted so as to be movable endwise, cam plates securedthereto` adapted, respectively, to engage the cam arms on said shafts,and an operating lever connected to said bar, said cam plates beingproportioned, respectively, to maintain all set stops in set positionduring the full setting stroke of the set lever.

23. A rolling mill installation as specified in claim 5, which alsocomprises a stop mechanism consisting of a series of movably supportedstops adapted, respectively, to arrest movement of slabs along saidreturn table when their following ends attain positions in which theywill clear t-he rolling mill, consisting of shafts rotatably mounted atthe under side of the return table, cam arms secured to said stop`shafts, a bar mounted so as toV be movable endwise, cam plates securedthereto adapted, respectively, tov engage the cam armson said shafts,and an operating le ver connected to said bar, said cam plates beingproportioned, respectively, to maintain les all set stops in setposition 'during the full setting stroke of the set lever, and the rela-`v tion being such that said stop blocks Will fall by gravity toinoperative position When their respective cam arms pass out ofengagement with their respective cam plates upon reverse movement of theset lever.,

24. A rolling` mill installation as specified in claim 5, in which thereturn table comprises a clutch-driven live roller and means renderedoperative by throwing out said Clutch for braking said roller to stopmovement of a slab resting thereon.

25. A. rolling mill installation as specified in olaim 5, in Which thereturn table comprises a clutch-driven live roller, the inertia of saidroller vvh-enV the clutch is thrown out operating as a brake to arrestmovement of a slab resting thereon. Y,

26. A slab Wheel for the purpose specified, consisting of a shaft,spaced series of arms secured thereto, each series Comprising the samenumber of arms all of which are tangent to a circle eoncentriovvith theaxis of the shaft.

In Witness that I claim t-he foregoing as my invention, I atix mysignature this tenth day of April, 1930.

MILLER A. MGCREARY.

